1. Field of the Invention
The present invention relates to a composite sliding member excellent in draw forming characteristics and wear resistance.
2. Description of the Related Art
Conventionally, composite sliding members used as a bearing member and the like are composed of metal wire mesh or expanded metal as a base having a void portion and surface covered and impregnated with a sliding member composition or a synthetic resin composition obtained from tetrafluoroethylene resin (hereinafter, referred to as PTFE) together with a filler such as graphite, molybdenum disulfide, glass fiber, thermosetting resin and the like. These composite sliding members have as an object, obtaining a good wear resistance and low friction coefficient.
The composite sliding member formed of the afore-said metal wire mesh or expanded metal covered and impregnated with the sliding member composition has achieved a fairly low friction coefficient and low wear amount. Nevertheless, under severe circumstances in which these composite sliding members have recently been used is taken into consideration, they do not always satisfy sliding property, in particular, wear resistance. Further, bearings having various shapes are difficult to produce from such composite sliding members by draw forming and the like.
This is because the PTFE resin used has a poor adhesion force with the base and when formed, crack or exfoliation is created between the PTFE resin and the base and thus the mechanical strength of the resulting sliding member is greatly lowered. Further, the PTFE resin also has a poor adhesion force with the filler and thus the sliding property is also lowered because the filler becomes lost.
An object of the present invention is to solve the aforesaid problems and provide a composite sliding member excellent in draw forming and sliding property, and in particular in wear resistance.